Watch-case



(No Model.)

E. C. FITCH.

WATCH GAS?.

No. 315,756. Patented A131214, 1885.

N. Pinius. Pumu-Lluwnwplwr. Mmmm". D c.

UNITED STATES PATENT QEEICE.

EZRA C. FITCH, OF NEVTON, MASSACHUSETTS.

WATCH-CASE.

SPECIFICATION forming part of Letters Patent No. 315,756, dated April 14, 1885.

Application filed October 1,1S4.

T0 @ZZ whom t may concern;

Be it known that I, EZRA G. Fi'roH, ot' Newton, in the county of Middlesex and State of Massachusetts, have invented certain Improvements in fateli-Cases, of which the following is a speciiication.

This invention relates, particularly, to that class of watch-cases in which the back or cover is attached to the body of the case by screwthreads; and it consists, as a whole, in a case having the central portion ofthe back or cover rigidly attached to the inner cap, the latter being connected by screw-threads, or otherwise,to the case-center, while the back or cover has no direct connection with the case-center, but is held in contacttherewith by the inner cap, the object being to enable the inner cap to protect the watch-movement, as usual, and at the same time stiffen and support the back or cover and reduce the number of separate pieces when the case is opened, the inner cap and back being handled as one piece, instead of two, as heretofore.

The invention also consists in a packing of leather or other suitable material inserted between the margins ot' the inner cap and ofthe back or cover to insure a dust-proof joint, all of which I will now proceed to describe.

Of the accompanying drawings, forming a part of this specification, Figure l represents a sectional View of a watch-case provided with my improvement, the inner cap being secured to the case-center. Fig. 2 represents a similar view, showing the inner cap connected to the case-center by a snap-edge. Figs. 3 and I represent sectional views of modifications.

Ihe same letters of reference indicate the same parts in all the gures.

In the drawings, a represents the case-center, and b the back or cover, and c the inner cap Within the back or cover.

Instead of forming the back and cap in two independent or separable parts, as heretofore, I forxn the cap so that it closely iits the contour of the inner surface of the back for a considerable distance outward from the center, and rigidly connect it to the central portion of the back, either by solder or by rivets, or by any other suitable means whereby a permanent connection is effected. This central bearing of the back against the cap enables (No model.)

the latter to stiften and support the former. The margin of the back is separated from the margin of the cap, as shown.

Instead of providing means for positively connecting the back and case-center, I form the margin of the back to simply bear against the case-center, and provide the margin of the cap either with screw-threads to engage with corresponding threads ou the case-center, as shown in Figs. I and 4, or on a movementholding ring, as shown in Fig. 3, or with a snap-edge to engage with a shoulder on the case-center, as shown in Fig. 2. I prefer the screw-threads, however, because they cause the margin ofthe back to be pressed lirmly against the case-center when the bach and cap are turned to screw the cap to place on the center. The screw-thread may be formed either on the exterior or the interior ofthe cap, and the corresponding thread may be formed either on the case-center, as shown in Fig. I, or on a movement-holding ring, d, as shown in Fig. 3. The baci; and cap are .formed with an annular space at their margins between the outer surface ol the cap and the inner surface of the back. Into this space is closely fitted a ring, e, of leather or other suitable material, for the purpose of securing an absolutely-tight joint ,between the back and center, said ring being pressed closely against the casecenter when the cap is screwed to place.

The described improvements are not limited to cases in which the back or cover is screwed on, but may be applied to cases having joints or hinges.

I clain1-- I. A watch-case having an inner cap provided with means, as described, for attachment to the case, and aback or cover secured to and bearing against the central portion of the cap, and separated from the cap at its margin, as set forth.

2. A watch-case having an inner cap which is threaded to engage with a corresponding thread on the case, and a back or cover secured to and bearing against the central portion of the cap, and separated from the cap at its margin, as set forth.

3. In a watch-case, the combination of the case-center provided with a screw-thread, the

inner cap threaded to enga-ge with the thread Ico of the ease-center7 and the back secured to l In testmonywhereofhave signedmyname and bearing centrally against the capl and to thisl specification, in the presence of two ro pressed by the latter against it seat on the subscribing Witnesses7 this 20th day of Sepease-center, as set forth. tember, 1884.

4. In a watch-case, the combination of the EZRA C. FITCH. case-center7 the connected back and cap hav- Vitnesses: ing the marginal annular space, andapacking- I. V. SKINNER, ring placed in said space, as set forth. l E. A. HARSH.' 

